For those of you having that problem on Ubuntu/Debian I noticed when installing php-pear from Aptitude it also installed php4-dev & php4-common which is causing these PDO errors on compile time... apt-get rmeove php4-dev php4-common then pecl install... Should fix it also note the php5-mysql package provides PDO

This problem is not bogus and is not a unbuntu issue. It happens on multiple vendor versions of Linux, Sunos and HPUX. I have seen it on all of them. After 3 days I finally figured it out: This problem is caused by an incompatibility between the embedded PDO in php and the PDO modules.
If you compile PHP with --disable-pdo and then use PEAR/PECL to add PDO and PDO_MYSQL, PDO_INFORMIX, etc., the all work well and it solves this issue.
I have done it on several versions of Linux and HPUX.
I just did it today with php-5.2.4:
PHP 5.2.4 (cli) (built: Jul 21 2008 21:19:07)
Copyright (c) 1997-2007 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2007 Zend Technologies
php -i |egrep "pdo|PDO"
Configure Command => './configure' '--disable-pdo' '--with-apxs2=/usr/local/apache2/bin/apxs' '--with-openssl=/usr' '--enable-force-cgi-redirect' '--with-gd' '--with-jpeg-dir=/usr/lib' '--with-zlib' '--enable-bcmath' '--enable-mbstring=all' '--with-curl'
PDO
PDO support => enabled
PDO drivers => mysql, informix
pdo_informix
pdo_informix support => enabled
pdo_mysql
PDO Driver for MySQL, client library version => 5.0.51a
Good Luck,
David
--
David Beecher, Sr. Engineer
TekOps, Inc.
http://www.tekops.com
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